In Dante's Paradiso, which figure does he encounter within the sphere of the Sun?

Explanation

In the Paradiso, Dante meets several important figures in different celestial spheres. Specifically, in the sphere of the Sun, he encounters Saint Thomas Aquinas, a renowned theologian and philosopher. Virgil appears earlier in the Divine Comedy, Judas is found in the Inferno, and Cacciaguida appears in the sphere of Mars.